Circuit architecture for distributed multiplexed control and element signals for phased array antenna

ABSTRACT

The phased array antenna system is described. The phased array antenna system formed on one or more layers of a printed circuit board (PCB). The phased array antenna system be may include a beam forming network to convert between one or more element signals and a beam signal. The phased array antenna system may include one or more control circuits, where each control circuit may receive the element signals for corresponding antenna element. Each of the control circuits may further may establish a control signal path and an element signal path between the antenna elements and the beamforming network, where the signal path may carry multiplexed element and control signals. The control circuits may include a signal adjustment circuit that may adjust the corresponding element signal (e.g., in phase or amplitude) based on the control signal.

CROSS REFERENCES

This application claims priority to U.S. Provisional Application No.62/648,527, entitled “MULTIPLEXED CONTROL AND RF SIGNALS ON BEAM FORMINGNETWORK,” which was filed on Mar. 27, 2018, the contents of which arehereby incorporated by reference herein in their entirety.

BACKGROUND

Phased array antennas may be used in some wireless communicationssystems. A phased array antenna may be configured to steer one or morebeams in different directions by way of manipulating phase and/oramplitude relationships of each individual antenna element of the phasedarray antenna. For example, the phased array antenna may be configuredto point one or more beams at a target during operation. In some cases,the phased array antenna may be mounted on a moving system, for example,a vehicle. In some cases, however, it may be desirable to keep theoverall cost of the antenna system relatively low. In these cases, acost-efficient and relatively compact architecture for phased arrayantennas that maintains robust performance may be desirable.

SUMMARY

A phased array antenna system is described. The phased array antennasystem may include a beam forming network to convert between one or moreelement signals at one or more element signal ports and a beam signal ata common signal port of the beam forming network. The beam formingnetwork may be located on one or more layers of a printed circuit board(PCB).

The phased array antenna system may include a first signal routingcircuit (e.g., a diplexer) to provide a control signal from a controllerto the element signal port, where the beam forming network maydistribute the control signal to each of the one or more element signalports. The phased array antenna system may include one or more controlcircuits located on a first layer of the PCB, where each control circuitmay include a first port coupled to a corresponding element signal portof the one or more element signal ports and a second port coupled to acorresponding antenna element. Respective antenna elements maycorrespond to respective control circuits located on a second layer ofthe PCB.

Each of the one or more control circuits may include a second signalrouting circuit (e.g., a second diplexer) coupled to the first port. Thesecond signal routing circuit may establish an element signal path for acorresponding element signal of the one or more element signalscommunicated between the first port and the second port. The secondsignal routing circuit may further establish a control signal path forthe control signal received via the first port. Each of the one or morecontrol circuits may further include a signal adjustment circuit alongthe element signal path and the control signal path. The signaladjustment circuit may adjust the corresponding element signal (e.g., inphase or amplitude) based on the control signal.

Further scope of the applicability of the described methods andapparatuses will become apparent from the following detaileddescription, claims, and drawings. The detailed description and specificexamples are given by way of illustration only, since various changesand modifications within the scope of the description will becomeapparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of embodiments ofthe present disclosure may be realized by reference to the followingdrawings. In the appended figures, similar components or features mayhave the same reference label. Further, various components of the sametype may be distinguished by following the reference label by a dash anda second label that distinguishes among the similar components. If onlythe first reference label is used in the specification, the descriptionis applicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 shows a diagram of a satellite communication system in accordancewith aspects of the present disclosure.

FIG. 2 illustrates an example diagram of a circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna in accordance with aspects of the present disclosure.

FIG. 3 shows an example diagram of a beam forming network for a circuitarchitecture for distributed multiplexed control and element signals fora phased array antenna in accordance with aspects of the presentdisclosure.

FIGS. 4-6 illustrate example diagrams of circuit architectures fordistributed multiplexed control and element signals for phased arrayantennas in accordance with aspects of the present disclosure.

FIG. 7 illustrates an example diagram of multi-layer printed circuitboard (PCB) for a circuit architecture for distributed multiplexedcontrol and element signals for a phased array antenna in accordancewith aspects of the present disclosure.

FIG. 8 illustrates an example diagram of an address decoder for acircuit architecture for distributed multiplexed control and elementsignals for a phased array antenna in accordance with aspects of thepresent disclosure.

DETAILED DESCRIPTION

The described features generally relate to a circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna. A phased array antenna may be configured to steer one or morebeams in different directions by way of manipulating phase and/oramplitude relationships of each individual antenna element of the phasedarray antenna. For example, the phased array antenna may be configuredto point one or more beams at a satellite (e.g., to actively track thesatellite) during operation. For some such applications, a relativelylow-cost architecture for phased array antennas that maintains robustperformance may be desirable. For example, cost-efficient phased arrayantennas may facilitate economic incorporation in satellite residentialuser terminal applications, commercial and individual automotiveapplications, etc. Further, in some applications, such as for UAVs andsmaller manned aircraft (e.g., regional and business jets), a relativelysmaller and more compact phased array antenna architecture mayfacilitate a relatively smaller, lighter, and/or more cost-efficientproduct.

One way to reduce the size and manufacturing cost of such phased arrayantennas is to reduce the size and manufacturing cost of the design of acontrol circuit architecture for the phased array antennas. A phasedarray antenna control circuit may be manufactured across one or morelayers of a printed circuit board (PCB). As complexity of the controlcircuit architecture and the number of printed layers of the PCBincreases, the overall manufacturing cost of the phased array antennawill also generally increase. A distributed control circuit architecturemay provide signal paths to multiple distributed control circuits andcorresponding antenna elements, where one signal path may be used tocarry a control signal for control circuits multiplexed with an elementsignal to or from the antenna element. This architecture may, forexample, use relatively fewer PCB layers, and may reduce the overallcomplexity and manufacturing cost of such PCB-based phased array antennasystems.

Techniques described herein may provide for a distributed controlcircuit architecture using a shared signal path carrying both controland element signals for each of one or more control circuits distributedalong the signal paths between a beam forming network and respectiveindividual antenna elements of the phased array antenna. In some cases,the phased array antenna may be a transmitting phased array antenna, areceiving phased array antenna, or perform the operations of both. Thebeam forming network may convert between a beam signal at a commonsignal port and one or more element signals at respective element signalports corresponding to particular antenna elements of the phased arrayantenna. For example, in the case of a transmitting phased arrayantenna, the beam forming network may convert a transmit beam signalinto multiple transmit element signals to be transmitted by respectiveantenna elements of the antenna array. Additionally or alternatively, inthe case of a receiving phased array antenna, the beam forming networkmay convert multiple receive element signals received by respectiveantenna elements of the antenna array into a receive beam signal.

The beam forming network may further distribute a control signalmultiplexed with the beam signal at the common signal port to therespective element signal ports corresponding to particular antennaelements of the phased array antenna. The control signal may be routedby the beam forming network to control circuits at the respectiveelement signal ports via respective signal paths. The control circuitsmay each have a first port connected via a signal path to a respectiveelement signal port of the beam forming network and a second portconnected via a signal path to a respective antenna element of theantenna array. In some cases, the control signal may be multiplexed withan element signal, for example, on the signal received at the first portof the control circuit from the element port of the beam formingnetwork. The control circuits may each be configured to extract thecontrol signal multiplexed with the element signal and to apply anadjustment to the element signal. In particular, the control circuitsmay include routing circuitry to establish a signal path for acorresponding element signal and a signal path for a correspondingcontrol signal each received via the first port of the control circuit.The control circuit may further include a signal adjustment circuitalong one or both paths to adjust the element signals based on therespective control signals. Accordingly, a single signal path passingthrough one respective control circuit from the beam forming network maybe used for both the control signals and the element signals for eachantenna element. Thus, PCB complexity, including a number PCB layers,may be reduced, lowering the manufacturing cost of the phased arrayantenna.

This description provides examples, and is not intended to limit thescope, applicability or configuration of embodiments of the principlesdescribed herein. Rather, the ensuing description will provide thoseskilled in the art with an enabling description for implementingembodiments of the principles described herein. Various changes may bemade in the function and arrangement of elements.

Thus, various embodiments may omit, substitute, or add variousprocedures or components as appropriate. For instance, it should beappreciated that the methods may be performed in an order different thanthat described, and that various steps may be added, omitted orcombined. Also, aspects and elements described with respect to certainembodiments may be combined in various other embodiments. It should alsobe appreciated that the following systems, methods, devices, andsoftware may individually or collectively be components of a largersystem, wherein other procedures may take precedence over or otherwisemodify their application.

FIG. 1 shows a diagram of a satellite communication system 100 inaccordance with aspects of the present disclosure. The satellitecommunication system 100 includes a satellite 105, a gateway 115, agateway antenna system 110, and an aircraft 130. The gateway 115communicates with one or more networks 120. In operation, the satellitecommunication system 100 provides for two-way communications between theaircraft 130 and the network 120 through the satellite 105 and thegateway 115.

The satellite 105 may be any suitable type of communication satellite.In some examples, the satellite 105 may be in a geosynchronous orgeostationary earth orbit (GEO). In other examples, any appropriateorbit (e.g., low earth orbit (LEO), medium earth orbit (MEO), etc.) forsatellite 105 may be used. The satellite 105 may be a multi-beamsatellite configured to provide service for multiple service beamcoverage areas in a predefined geographical service area. In someexamples, the satellite communication system 100 includes multiplesatellites 105.

The gateway antenna system 110 may be two-way capable and designed withadequate transmit power and receive sensitivity to communicate reliablywith the satellite communication system 100. The satellite communicationsystem 100 may communicate with the gateway antenna system 110 bysending and receiving signals through one or more beams 150. The gateway115 sends and receives signals to and from the satellite communicationsystem 100 using the gateway antenna system 110. The gateway 115 isconnected to the one or more networks 120. The networks 120 may includea local area network (LAN), metropolitan area network (MAN), wide areanetwork (WAN), or any other suitable public or private network and maybe connected to other communications networks such as the Internet,telephony networks (e.g., Public Switched Telephone Network (PSTN),etc.), and the like.

The aircraft 130 includes an on-board communication system including anantenna array 140, for example, arrays of patch antennas. The on-boardcommunication system of the aircraft 130 may provide communicationservices for communication devices of the aircraft 130 via a modem (notshown). Communication devices may connect to and access the networks 120through the modem. For example, mobile devices may communicate with oneor more networks 120 via network connections to modem, which may bewired or wireless. A wireless connection may be, for example, of awireless local area network (WLAN) technology such as the Institute ofElectrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), or otherwireless communication technology.

The aircraft 130 may use the antenna array 140 to communicate with thesatellite 105 over one or more beams 160. The antennas array 140 may bemounted on the outside of the fuselage of the aircraft 130. In somecases, the antenna array 140 be a phased array antenna. Phased arrayantennas may be configured to steer the one or more beams 160 inparticular directions by way of manipulating phase and/or amplituderelationships of individual antennas of the phased array antenna. Forexample, the antenna array 140 may be configured to point the one ormore beams 160 at the satellite (e.g., to actively track the satellite)during operation. The antenna array 140 may be used for receivingcommunication signals from the satellite 105, transmitting communicationsignals to the satellite 105, or bi-directional communication with thesatellite 105 (i.e., transmitting and receiving communication signals).The antenna array 140 may operate in the InternationalTelecommunications Union (ITU) Ku, K, or Ka-bands, for example fromapproximately 17 to 31 Giga-Hertz (GHz). Alternatively, the antennaarray 140 may operate in other frequency bands such as C-band, X-band,S-band, L-band, and the like. Although a single antenna array 140 isillustrated, more than one antenna array 140 may be used forcommunication, in some cases.

The antenna array 140 may be within a housing or enclosure, which mayprotect the antenna array 140 from environmental elements and may beconstructed of a material or materials that do not substantiallyattenuate communication signals. Additionally, the antenna array 140 maybe used in other applications besides onboard the aircraft 130, such asonboard boats, vehicles, or on ground-based stationary systems. For somesuch applications, a relatively low-cost architecture for phased arrayantennas that maintains robust performance may be desirable. Forexample, cost-efficient phased array antennas may facilitate economicincorporation in satellite residential user terminal applications,commercial and individual automotive applications, etc. Further, in someapplications, such as for UAVs and smaller manned aircraft (e.g.,regional and business jets), a relatively smaller and more compactphased array antenna architecture may facilitate a relatively smaller,lighter, and/or more cost-efficient product. For example, the housingfor a phased array antenna may be substantially smaller than a radomeused for a mechanically gimballed passive antenna array.

One way to reduce the size and manufacturing cost of such phased arrayantennas is to reduce the size and manufacturing cost of the design of acontrol circuit architecture for the phased array antennas. A phasedarray antenna control circuit may be manufactured across one or morelayers of a PCB. As complexity of the control circuit architecture andthe number of printed layers of the PCB increases, the overallmanufacturing cost of the phased array antenna will also generallyincrease. A distributed multiplexed control and element signalarchitecture may multiplex control signals for multiple distributedcontrol circuits and corresponding antenna elements with an elementsignal for transmission or reception via the antenna elements on thesame signal paths. This architecture may, for example, use relativelyfewer PCB layers, and may reduce the overall complexity andmanufacturing cost of such PCB-based phased array antenna systems.

Techniques described herein provide for a distributed multiplexedcontrol and element signal architecture using a shared signal pathcarrying both control and element signals for each of one or morecontrol circuits distributed along the signal paths between a beamforming network and respective individual antenna elements of the phasedarray antenna. In the described distributed multiplexed control andelement signal architecture, the signal paths may carry a control signalincluding control data for the control circuits multiplexed (e.g., viafrequency-domain multiplexing (FDM), and the like) with element signals(i.e., radio frequency (RF) signals) for transmission or reception viathe respective antenna elements. In doing so, a single signal path maybe used for both the control and the element signals for each antennaelement, rather than, for example, having separate dedicated control andelement signal paths. For example, as further described below, a singlesignal path may carry control information multiplexed with elementsignals sent to or from corresponding antenna elements. For instance,the control signal may be multiplexed with a transmit element signal inthe same direction from the beamforming network. Alternatively, thecontrol signal may be multiplexed with receive element signals combinedin the beamforming network. According to the described techniques, PCBcomplexity, including a number PCB layers, may be reduced, lowering themanufacturing cost of the phased array antenna.

FIG. 2 illustrates an example diagram 200 of a circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna in accordance with aspects of the present disclosure. The phasedarray antenna may be an example of one or more of the antenna arrays140, as described with reference to FIG. 1. The phased array antenna ofFIG. 2 may be an example of a transmit phased array antenna fortransmitting communication signals to the satellite 105, as describedwith reference to FIG. 1.

As shown in FIG. 2, the circuit architecture includes a first routingcircuit 205-a, a beam forming network 210-a, multiple control circuits215, and multiple antenna elements 220. In the example of FIG. 2, afirst control circuit 215-a and a corresponding first antenna element220-a and a second control circuit 215-b and a corresponding secondantenna element 220-b are shown. It should be appreciated, however, thatany number N of control circuits 215 for antenna elements 220 may beimplemented similarly. Hence, the first control circuit 215-a may attimes be referred to as “control circuit 1,” and the second controlcircuit 215-b may at times be referred to as “control circuit N.”Element signals communicated via the antenna elements 220 may bearranged to form an antenna beam with desired characteristics (e.g.,individual element signals communicated via each antenna element 220 maybe configured with a particular phase and/or amplitude relative toindividual element signals communicated via other antenna elements 220to steer the antenna beam in a desired direction). As illustrated inFIG. 2, there is a one-to-one correspondence between control circuits215 and antenna elements 220 (i.e., there is a different control circuit215 connected to each antenna element 220). However, it is to beappreciated that in some cases one control circuit 215 may be sharedamong multiple antenna elements 220 (i.e., one control circuit 215 maybe connected to, and provide respective signaling to, multiple antennaelements 220).

As described above, the phased array antenna may be a PCB-based antennasystem in which the phased array antenna and corresponding controlarchitecture are printed or otherwise formed on one or more layers of aPCB. A PCB may include signal paths across one or more PCB layers (e.g.,conductive lines, traces, vias connecting traces on different PCBlayers, or planes). For example, a signal path may include a PCBtransmission line made up of one or more conductive lines and a groundplane or ground lines. As described herein, a layer may refer to asingle layer of conductive material (which may include conductive linesand/or one or more ground planes and/or one or more ground lines). Forexample, a “two-layer PCB” may include two layers of conductive materialseparated by a dielectric substrate, a “four-layer PCB” may include fourlayers of conductive material separated by three dielectric substrates,etc.). The number of layers of conductive signal lines and ground linesor planes that form a transmission line within a PCB may vary based on atype of the transmission line (e.g., microstrip, stripline, coplanarwaveguide etc.). For example, a transmission line in a PCB may includeone conductive line layer and one or more ground lines or planes withinthe same layer as the conductive line layer, or in different layers. Thesignal paths may carry signals, such as control signals, beam signals,element signals, and the like, between the connected components orports, and signal paths may include one or more PCB transmission linesthat are within the same or different layers.

When configured as a transmit phased array antenna, the phased arrayantenna may be configured to transmit a beam at a desired scan angledirection relative to boresight (e.g., in a direction to track a targetsatellite). The first routing circuit 205-a (e.g., a diplexer or othermultiplexer, or other type of signal routing circuit) may receive atransmit beam signal 236-a from, for example, a transmission processor,to be transmitted as a transmit beam by the phased array antenna. Thefirst routing circuit 205-a may further receive control data 226-a froma controller 225-a. The control data 226-a may indicate adjustmentvalues (e.g., amplitude and/or phase) for one or more of the N controlcircuits 215 to be applied by respective control circuits (as discussedbelow) to transmit the transmit beam in a desired scan angle direction.

The phased array antenna may include a modulator 230-a (e.g., anamplitude shift keying (ASK), or phase shift keying (PSK) modulator)that modulates the control data 226-a to produce a control signal 231-a.The modulator 230-a may modulate the control data 226-a received fromthe controller 225-a and pass the modulated control signal 231-a to thefirst routing circuit 205-a. In some cases, the modulator 230-a may beimplemented within or as a component of the controller 225-a. In somecases, the control signal 231-a and the transmit beam signal 236-a mayoccupy different, non-overlapping frequency ranges. The multiplexer ofthe first routing circuit 205-a may multiplex the transmit beam signal236-a (having a center frequency f_(tx)) and the control signal 231-a(having a center frequency f_(c)) using, for example, FDM, to generate acomposite multiplexed signal 241-a including the transmit beam signal236-a and the control signal 231-a. Different possible implementationsfor the are first routing circuit 205-a may be used. For example, inFIG. 2, the first routing circuit 205-a is a diplexer (i.e., amultiplexer with two inputs) including two bandpass filters 235—one foreach input. The first bandpass filter 235-a may allow signals of a firstfrequency range to pass, where the first frequency range corresponds toat least a frequency range of the transmit beam signal 236-a. Thetransmit beam signal 236-a may be, for example, a modulated transmitbeam signal, with a modulating transmit signal beam signal modulatedwith a carrier frequency f_(tx) for the transmit beam signal. Althoughshown having a center frequency equal to f_(tx), the center frequency ofthe first bandpass filter may not be the same as the carrier frequencyf_(tx) for the transmit beam signal, as long as the first frequencyrange allows the transmit beam signal 236-a to pass (e.g., whileexcluding the control signal 231-a). The second bandpass filter 235-bmay allow signals within a second frequency range to pass, where thesecond frequency range corresponds to at least a frequency range of thecontrol signal 231-a. The control signal 231-a may be, for example, amodulated control signal, with control data 226-a modulated with acarrier frequency f_(c) for the control signal, where the carrierfrequency for the control signal is different from the carrier frequencyfor the transmit beam signal. Although shown having a center frequencyequal to f_(c), the center frequency of the second bandpass filter maynot be the same as the carrier frequency f_(c) for the control signal,as long as the second frequency range allows the control signal 231-a topass (e.g., while excluding the transmit beam signal 236-a).

Alternatively, in other embodiments in which the carrier of the controlsignal 231-a is of a lower frequency than the carrier of the transmitbeam signal 236-a, a high-pass signal path may be formed in place of thefirst bandpass filter 235-a, and a low-pass signal path may be used inplace of the second bandpass filter 235-b. The high-pass signal path maybe formed (e.g., using PCB traces) that allows signals within a higherfrequency range to pass, where the higher frequency range is sufficientfor the transmit beam signal 236-a (e.g., the modulated transmit beamsignal). The low-pass signal path may be formed (e.g., using componentssuch as capacitors and inductors) to allow signals within a lowerfrequency range to pass, where the lower frequency range is sufficientfor the control signal 231-a (e.g., the modulated control signal).

The first routing circuit 205-a may provide the composite multiplexedsignal 241-a, including the transmit beam signal 236-a multiplexed withthe control signal 231-a, to a common signal port 240-a of the beamforming network 210-a. The beam forming network 210-a may include one ormore stages of PCB dividers (e.g., equal-way and/or unequal way,in-phase and/or out-of-phase, or a combination) that divide thecomposite multiplexed signal 241-a to produce individual output signals246 (e.g., output signal 246-a and output signal 246-b) at correspondingoutput element signal ports 245 (e.g., element signal port 245-a andelement signal port 245-b) of the beam forming network 210-a. That is,the beam forming network 210-a may divide the composite multiplexedsignal 241-a into individual output signals 246, each individual outputsignal 246 including an individual element signal and an individualcontrol signal that are copies of the transmit beam signal 236-a and thecontrol signal 231-a, respectively. The one or more stages of PCBdividers may provide relative amplitude and/or phase shifts between theindividual element signals of the individual output signals 246 as partof the overall beamforming of the phased array antenna. In such a case,the individual control signals of the individual output signals 246 mayalso experience relative amplitude and/or phase shifts due to the one ormore stages of PCB dividers. However, such relative shifts in amplitudeand/or phase shifts are applied to the carriers of the individualcontrol signals and thus do not impact the control data 226-a. Inaddition, these shifts may not impact recovery of the carrier of theindividual control signals for synchronization (as discussed below), asthe precision needed may be significantly less than is needed for theindividual element signals. The control data 226-a may includeinformation for each of the control circuits 215 (e.g., serial data),and the beam forming network 210-a may copy the control data 226-a(e.g., by dividing the composite multiplexed signal 241-a including thecontrol signal 231-a carrying the control data 226-a) to each of theelement signal ports 245 corresponding to each of the antenna elements220. The individual element signals included in each individual outputsignal 246 at the respective element signal ports 245 may subsequentlybe adjusted by a corresponding control circuit 215 connected to thecorresponding element signal port 245 and transmitted by a correspondingantenna element 220.

Each of the individual output signals 246 at the element signal ports245 may include an individual element signal (e.g., a copy of thetransmit beam signal 236-a) multiplexed with an individual controlsignal (e.g., a copy of the control signal 231-a). The individualcontrol signal may be used by the corresponding control circuit 215 toapply an appropriate adjustment (e.g., amplitude and/or phase) to thecorresponding individual element signal. That is, the beam formingnetwork 210-a may divide the composite multiplexed signal 241-a togenerate individual output signals 246 at each element signal port 245,which each include an individual control signal and an individualelement signal. By multiplexing the beam signal and the control signal,the beam forming network 210-a may be used to generate and distributethe element signals and the control signals indicating control data forthe corresponding element signal for each control circuit 215. In doingso, a single signal path may be used for both the control and theelement signals for each antenna element in the beam forming network210-a, rather than, for example, having separate dedicated control andelement lines. Thus, PCB complexity, including a number PCB layers, maybe reduced, lowering the manufacturing cost of the phased array antenna.

Each control circuit 215 may include a first port 248 (e.g., first port248-a and first port 248-b) connected to a corresponding element signalport 245 of the beam forming network 210-a and a second port 249 (e.g.,second port 249-a and second port 249-b) connected to a correspondingantenna element 220 (or, in some cases, multiple antenna elements 220).Each control circuit 215 may include a second routing circuit 250 (e.g.,a diplexer or other multiplexer, or other type of signal routingcircuit) that establishes an element signal path 251 (e.g., elementsignal path 251-a and element signal path 251-b) between the first port248 and the second port 249 of the control circuit 215 and a controlsignal path 252 (e.g., control signal path 252-a and control signal path252-b) between the first port 248 of the control circuit 215 and anadjustment circuit 265.

As shown in FIG. 2, each of the second routing circuits 250 is adiplexer that demultiplexes (e.g., via frequency demultiplexing) thereceived individual output signal into corresponding individual elementand control signals. As correspondingly described with reference to thefirst routing circuit 205-a that multiplexes signals, the second routingcircuit 250 may perform analogous inverse operations using analogouscomponents to demultiplex the signals. For example, the second routingcircuit 250-a may include a first bandpass filter 235-c and a secondbandpass filter 235-d for the element signal and control signal,respectively. That is, the first bandpass filter 235-c may allow signalswithin a first frequency range to pass, where the first frequency rangecorresponds to at least a frequency range of the element signal (e.g.,the modulated transmit beam signal). Although shown having a centerfrequency equal to f_(tx), the center frequency of the first bandpassfilter 235-c may not be the same as the carrier frequency f_(tx) for theelement signal, as long as the first frequency range allows the elementsignal to pass (e.g., while excluding the control signal 231-a). Thesecond bandpass filter 235-d may allow signals within a second frequencyrange to pass, where the second frequency range corresponds to at leasta frequency range of the control signal 231-a (e.g., the modulatedcontrol signal). Although shown having a center frequency equal tof_(c), the center frequency of the second bandpass filter 235-d may notbe the same as the carrier frequency f_(c) for the control signal, aslong as the second frequency range allows the control signal 231-a topass (e.g., while excluding the element signal). Similarly, the secondrouting circuit 250-b may include a first bandpass filter 235-e and asecond bandpass filter 235-f for the element signal and control signal,respectively. As described above with reference to the first routingcircuit 205, other potential implementations may be used, including theuse of other PCB traces, components including high- and low-passfilters, capacitors, inductors, and the like.

In the first control circuit 215-a, the control signal path 252-a mayprovide the control signal to a demodulator 255-a and an address decoder260-a. The demodulator 255-a may demodulate the control signal carriedon the control signal path 252-a to obtain control information. Thecontrol information may include commands for each of the controlcircuits 215 that are distributed to each of the control circuits 215 bythe beam forming network 210-a. The commands for different controlcircuits 215 may be serially transmitted in the control information.That is, in addition to receiving its own control data, the controlcircuit 215-a may receive and demodulate the control information foreach of the other control circuits 215 (e.g., for control circuit215-b). The control information may include address information (e.g.,in a header) identifying the address of the particular control circuit215 for which the corresponding control information is intended. Theaddress decoder 260-a may compare a known address (as further discussedbelow) of the control circuit 215-a to the address information in thecontrol data 226-a to identify the control information that is intendedfor the particular control circuit 215-a, and provide the identifiedcontrol information via a signal path 253-a to a correspondingadjustment circuit 265-a. The second control circuit 215-b may operatesimilarly to the first control circuit 215-a, the second control circuit215-b similarly including a demodulator 255-b, an address decoder 260-b,and an adjustment circuit 265-b (e.g., to similarly provide identifiedcontrol information via a signal path 253-b to the adjustment circuit265-b).

Each of the adjustment circuits 265 (e.g., adjustment circuit 265-a andadjustment circuit 265-b) may include one or more circuit elements(e.g., one or more phase shifters 270, one or more amplifiers 275, etc.)to provide, based on the identified control information (e.g., beamcoefficients, etc.), appropriate adjustments of amplitude and/or phaseto the corresponding element signals. FIG. 2 shows a breakout view ofthe adjustment circuit 265-a. In the illustrated example, the adjustmentcircuit 265-a includes a phase shifter 270-a that applies a phase shiftto the corresponding element signal as indicated by the controlinformation. In the illustrated example, the adjustment circuit 265-afurther includes an amplifier 275-a that amplifies the phase shiftedsignal from the phase shifter as indicated by the control information toproduce an adjusted element signal. The adjusted element signal may beprovided via the second port 249 of the control circuit 215 to thecorresponding antenna element 220 for transmission. The adjustmentcircuit 265-a may operate similarly to adjust and provide the elementsignal to the second antenna element 220-b. The transmissions of theadjusted element signals by each of the antenna elements 220 of thephase array antenna together produce a transmit beam transmitted in adesired scan angle direction (e.g., in a direction of a targetsatellite, or other receiving device).

Different techniques for assigning addresses and techniques by which theaddress decoders 260 of each of the control circuits 215 may determinetheir correspondingly assigned addresses are described. In one exampleimplementation, each of the control circuits 215 may be identical acrossthe antenna array. As such, the particular control circuits 215 may nothave preconfigured information or other differentiable information orfeatures that could be used to determine their correspondingly assignedaddresses prior to installation at their respective locations on theantenna array PCB. In this case, the various locations on the arrayantenna PCB may include different features indicating an addressingscheme across the array. These features may be used by the addressdecoders 260 to determine the addresses assigned to its correspondingcontrol circuit 215.

In one example implementation, the addresses of the control circuits 215may be set using pull-up/down or open/short address strapping. Forexample, a particular control circuit 215 may include multiple addresspins and be placed at a particular location on the antenna array PCB. Insome cases, a default configuration for the address pins may be pulledup (e.g., via an internal resistor of the control circuit 215) and,according to a location on the PCB, a unique combination of groundedvias may pull down particular address pins. For example, a first set ofaddress pins may correspond to a row address of the control circuit 215and a second set of pins may correspond to a column address of thecontrol circuit 215. The resulting sequence of pulled up and pulled downaddress pins may then indicate the unique address for that controlcircuit 215.

Additionally or alternatively, each control circuit 215 may recognizeits own address by reading address voltage levels, for example using ananalog-to-digital converter (ADC). For example, as further describedwith reference to FIG. 8, voltage divider elements (e.g., resistervoltage dividers) for each of the rows and columns may divide the supplyvoltage and corresponding row and column voltages may be read by ADCs atthe control circuits 215. The antenna array PCB may include one voltagedivider element per row that divides the supply voltage to acorresponding row voltage indicating a particular row and one voltagedivider element per column that divides the supply voltage to acorresponding column voltage indicating the column. Each control circuit215 may then include a row address pin that receives the correspondingrow voltage and a column address pin that receives the correspondingcolumn voltage. ADCs may then be used to read these voltages at the rowand column address pins. Doing so may reduce a number of resistors to beused versus some other techniques. In addition, this describedimplementation may use a relatively lower pin-count versus usingpull-up/down or open/short address strapping, which may reduce PCB areaor cost for each control circuit 215.

In some cases, the addresses of the control circuits 215 may be selected(e.g., using sequential row and column addresses) such that if a controlcircuit applies control information (e.g., particular beam adjustmentcoefficients for amplitude and/or phase) for an incorrectly decodedaddress, the control information applied by the control circuit islikely intended for one of the adjacent control circuits 215. In somecases, the row and column addressing may ensure that the addresses ofsuccessive rows or columns do not differ by more than one bit (e.g., aHamming distance equal to one (1)), and that any two rows or columnsthat are not consecutive have more than one bit that is different (e.g.,a Hamming distance greater than one (1)). In this case, if a controlcircuit 215 incorrectly decodes the address as a result of a single-biterror, the control circuit 215 would apply an adjustment (e.g., of phaseand/or amplitude) intended for its nearest neighboring control circuit215 by row and/or column, which may not substantially degrade the RFbeam forming performance of some antenna arrays. For example, this maybe a similar performance as a group of antenna elements of the antennaarray being twice as large as if the wrong address were not used in theantenna array. In some cases, the address of the control data may beencoded with one or more error correction bits to reduce the likelihoodof incorrect address decoding. For example, the address of the controldata may be transmitting according to a linear block code such as aHamming code, Reed-Solomon code, and the like.

In some cases, the control circuits 215 and the controller 225-a maysupport bi-directional communication. For example, each of the controlcircuits 215 may also have a modulator (not shown), which may be part ofthe demodulator 255, or a separate component. Controller 225-a may senda command to read a configured value (e.g., control information) fromone of the control circuits 215, and the addressed control circuit 215may then respond by modulating a signal with the response (e.g., theconfigured value) and multiplexing the modulated signal onto theindividual output signal 246 at the respective element signal port 245.The modulated signal may then be carried via the beam forming network210-a and the first routing circuit 205-a to the controller 225-a, whichmay then demodulate the signal and decode the response. Thus,bi-directional communication may allow for checking a configuration ofthe control circuits 215, or reading other status information from thecontrol circuits 215 for testing or debugging purposes.

In some cases, the demodulators 255 may recover the carrier (e.g., acarrier for the control signal) to generate a clock signal tosynchronize the different control circuits 215. For example, thedemodulator 255-a may use a carrier-recovery loop or other carrierrecovery techniques (e.g., compensating for frequency and/or phasedifferences between the control signal carrier and a local oscillator).The demodulator 255-a may then set a clock signal based on the recoveredwaveform. In this way, the clock signal may be synchronized between eachof the control circuits 215 of the phased array antenna. Thus, thecontrol signal may use coherent modulation, and the synchronized clocksignals at the demodulators 255 may use coherent demodulation todemodulate the control signal 231-a.

FIG. 3 shows an example diagram 300 of a beam forming network 305 for acircuit architecture for distributed multiplexed control and elementsignals for a phased array antenna in accordance with aspects of thepresent disclosure. The beam forming network shown in FIG. 3 may be anexample of the beam forming networks described at least with referenceto FIGS. 2 and 4 through 7.

The beam forming network 305 shows a common port 310, which may be anexample of the input common signal port as described with reference toFIG. 2. The beam forming network 305 also shows several element ports315, labeled “Element Port 1” to “Element Port N,” which may correspondto a number of control circuits 1 to N, as described with reference toFIG. 2. The element ports 315 may be examples of the element signalports as described with reference to FIG. 2.

The example diagram 300 of the beam forming network 305 shows threestages of combiner/dividers (e.g., PCB combiner/dividers formed in aPCB). That is, an input signal received at the common port 310 may bedivided a first time to two signals, then each signal may be divided twomore times in sequence to generate output signals at the eight shownelement ports 315. Conversely, signals received at the eight elementports 315 may be combined by the beam forming network 305 to form acombined signal at the common port 310. In some cases, thesecombiner/dividers may be equal-way and/or unequal way, in-phase and/orout-of-phase, or any combination. It is to be appreciated, however, isjust one example network of PCB combiner/dividers, and that the beamforming network 305 may include either fewer or a greater number of suchcombiner/dividers in various configurations.

FIG. 4 illustrates an example diagram 400 of a circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna in accordance with aspects of the present disclosure. The phasedarray antenna may be an example of one or more of the antenna arrays140, as described with reference to FIG. 1, and the circuit architecturefor distributed multiplexed control and element signals for a phasedarray antenna as described with reference to FIG. 2. The phased arrayantenna of FIG. 4 may be an example of a transmit phased array antennafor transmitting communication signals to the satellite 105, asdescribed with reference to FIG. 1, and the circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna as described with reference to FIG. 2.

The circuit architecture for the phased array antenna in FIG. 4 mayoperate in substantially the same way with similar or correspondingcomponents as described with reference to FIG. 2, except as otherwisedescribed herein. In FIG. 4, the phased array antenna, in additional tocarrying beam, element, and control signals, includes a power source 405that generates a power signal 408 that may be carried on the signalpaths and multiplexed with the beam, element, and control signals.

As shown in FIG. 4, the circuit architecture includes a first routingcircuit 205-b, a beam forming network 210-b, multiple control circuits215, and multiple antenna elements 220. In the example of FIG. 4, afirst control circuit 215-c and a corresponding first antenna element220-c and a second control circuit 215-d and a corresponding secondantenna element 220-d are shown. It should be appreciated, however, thatany number N of control circuits 215 for antenna elements 220 may beimplemented similarly. As illustrated in FIG. 4, there is a one-to-onecorrespondence between control circuits 215 and antenna elements 220(i.e., there is a different control circuit 215 connected to eachantenna element 220). However, it is to be appreciated that in somecases one control circuit 215 may be shared among multiple antennaelements 220 (i.e., one control circuit 215 may be connected to, andprovide respective signaling to, multiple antenna elements 220). Each ofthe components may be connected via signal paths.

The first routing circuit 205-b (e.g., a diplexer or other multiplexer,or other type of signal routing circuit) may receive a transmit beamsignal 236-b from, for example, a transmission processor, to betransmitted as a transmit beam by the phased array antenna. The firstrouting circuit 205-b may further receive control data 226-b from acontroller 225-a. The control data 226-b may indicate adjustment values(e.g., amplitude and/or phase) for one or more of the N control circuits215 to be applied by respective control circuits to transmit thetransmit beam in a desired scan angle direction.

The phased array antenna may include a modulator 230-b that modulatesthe control data 226-b to produce a control signal 231-b. The modulator230-b may modulate the control data 226-b received from the controller225-b and pass the modulated control signal 231-b to the first routingcircuit 205-b. In some cases, the modulator 230-b may be implementedwithin or as a component of the controller 225-b. The multiplexer of thefirst routing circuit 205-b may multiplex the transmit beam signal 236-b(having a center frequency f_(tx)) and the control signal 231-b (havinga center frequency f_(c)) to generate a composite multiplexed signal241-b including the transmit beam signal 236-b and the control signal231-b. In FIG. 4, the first routing circuit 205-b is a diplexerincluding two bandpass filters 235—one for each input. The firstbandpass filter 235-g may allow signals within a first frequency rangeto pass, where the first frequency range corresponds to at least afrequency range of the transmit beam signal 236-b (e.g., the modulatedtransmit beam signal). Although shown having a center frequency equal tof_(tx), the center frequency of the first bandpass filter 235-g may notbe the same as the carrier frequency f_(tx) for the transmit beamsignal, as long as the first frequency range allows the transmit beamsignal 236-b to pass (e.g., while excluding the control signal 231-b).The second bandpass filter 235-h may allow signals within a secondfrequency range to pass, where the second frequency range corresponds toat least a frequency range of the control signal 231-b (e.g., themodulated control signal). Although shown having a center frequencyequal to f_(c), the center frequency of the second bandpass filter 235-hmay not be the same as the carrier frequency f_(c) for the controlsignal, as long as the second frequency range allows the control signal231-b to pass (e.g., while excluding the transmit beam signal 236-b).Different possible implementations for the first routing circuit 205-bmay be used, as described above.

The first routing circuit 205-b may further receive the power signal 408from the power source 405. In FIG. 4, the power source 405 (e.g., a DCsource, or otherwise a voltage source or a current source) produces thepower signal 408 (e.g., a DC signal). The power signal 408 may passthrough an inductor 410-a (or another type of choke element) within thefirst routing circuit 205-b. The inductor may block the control signal231-b and the transmit beam signal 236-b from flowing through the signalpath to the power source 405. The first routing circuit 205-b mayfurther include a blocking capacitor 415-a that blocks the power signal408 from the signal paths of the beam signal 236-b and control signal231-b. The first routing circuit 205-b may output a compositemultiplexed signal 241-b including each of the transmit beam signal236-b, the control signal 231-b, and the power signal 408.

The first routing circuit 205-b may provide the composite multiplexedsignal 241-b, including the transmit beam signal 236-b multiplexed withthe control signal 231-b, to the common signal port 240-b of the beamforming network 210-b. The beam forming network 210-b may include one ormore stages of PCB dividers that divide the composite multiplexed signal241-b to produce individual output signals 246 (e.g., output signal246-c and output signal 246-d) at corresponding output element signalports 245 (e.g. element signal port 245-c and element signal port 245-d)of the beam forming network 210-b. That is, the beam forming network210-b may divide the composite multiplexed signal 241-b into individualoutput signals 246, each individual output signal 246 including anindividual element signal and an individual control signal that arecopies of the transmit beam signal 236-b and the control signal 231-brespectively. The one or more stages of PCB dividers may providerelative amplitude and/or phase shifts between the individual elementsignals of the individual output signals 246 as part of the overallbeamforming of the phased array antenna. In such a case, the individualcontrol signals of the individual output signals 246 may also experiencerelative amplitude and/or phase shifts due to the one or more stages ofPCB dividers. However, such relative shifts in amplitude and/or phaseshifts are applied to the carriers of the individual control signals andthus do not impact the control data 226-b. In addition, these shifts maynot impact recovery of the carrier of the individual control signals forsynchronization (as discussed below), as the precision needed may besignificantly less than is needed for the individual element signals.The control data 226-b may include information for each of the controlcircuits 215 (e.g., serial data), and the beam forming network 210-b maycopy the control data 226-b received at the common signal port 240-b(e.g., by dividing the composite multiplexed signal 241-b including thecontrol signal 231-a carrying the control data 226-b) to each of theelement signal ports 245 corresponding to each of the antenna elements220. The individual element signals included in each individual outputsignal 246 at the respective element signal ports 245 may subsequentlybe adjusted by a corresponding control circuit 215 connected to thecorresponding element signal port 245 and transmitted by a correspondingantenna element 220.

Each of the individual output signals 246 at the element signal ports245 may include an individual element signal (e.g., a copy of thetransmit beam signal 236-b) multiplexed with an individual controlsignal (e.g., a copy of the control signal 231-b), and the power signal408. The control signal may be used by the corresponding control circuit215 to apply appropriate adjustment (e.g., amplitude and/or phase) tothe corresponding element signal. That is, the beam forming network210-b may divide the composite multiplexed signal 241-b to generateindividual control signals and individual element signals at eachelement signal port 245. The individual control signals may bemultiplexed with the corresponding element signals to form themultiplexed individual output signals 246. By multiplexing the beamsignal and the control signal, the beam forming network 210-b may beused to generate and distribute the element signals and the controlsignals indicating control data for the corresponding element signal foreach control circuit 215.

Each control circuit 215 may include a first port 248 (e.g., first port248-c and first port 248-d) connected to a corresponding element signalport 245 of the beam forming network 210-b and a second port 249 (e.g.,second port 249-c and second port 249-d) connected to a correspondingantenna element 220. Each control circuit 215 may include a secondrouting circuit 250 (e.g., a diplexer or other multiplexer, or othertype of signal routing circuit) that establishes an element signal path251 (e.g., element signal path 251-c and element signal path 251-d)between the first port 248 and the second port 249 of the controlcircuit 215 and a control signal path 252 (e.g., control signal path252-c and control signal path 252-d) between the first port 248 of thecontrol circuit 215 and an adjustment circuit 265.

As shown in FIG. 4, each of the second routing circuits 250 is adiplexer that demultiplexes the received individual output signal intocorresponding individual element and control signals. As correspondinglydescribed with reference to the first routing circuit 205-b thatmultiplexes signals, the second routing circuits 250 may performanalogous inverse operations using analogous components to demultiplexthe signals. For example, the second routing circuit 250-c may include afirst bandpass filter 235-i and a second bandpass filter 235-j for theelement signal and control signal, respectively. Similarly, the secondrouting circuit 250-d may include a first bandpass filter 235-k and asecond bandpass filter 235-l for the element signal and control signal,respectively. Although shown having a center frequency equal to f_(tx),the center frequency of the first bandpass filters 235-i and 235-k maynot be the same as the carrier frequency f_(tx) for the transmit beamsignal, as long as they allow the element signal to pass (e.g., whileexcluding the control signal). Similarly, the center frequency of thesecond bandpass filters 235-j and 235-l are shown as equal to f_(c), butmay not be the same as the carrier frequency f_(c) for the controlsignal, as long as they allow the control signal to pass (e.g., whileexcluding the element signal). Different possible implementations forthe second routing circuits 250 may be used, as described above,including, for example, the use of other PCB traces, componentsincluding high- and low-pass filters, capacitors, inductors, and thelike.

In some cases, each of the control circuits 215 may include a decouplerthat decouples the multiplexed power signal to obtain the power signalfor supplying power to control circuits 215 and other components. Thesecond routing circuits 250 within each of the control circuits 215 mayinclude inductors 410 (e.g., inductor 410-b and inductor 410-c), oranother type of choke element, that allows the power signal to pass,which may then be provided to various other components of the controlcircuit 215 to provide the other components power. The second routingcircuits 250 may further include blocking capacitors 415 (e.g.,capacitor 415-b and capacitor 415-c) that block the power signal 408from the signal paths to the respective antenna elements 220.

In, for example, the first control circuit 215-c, the control signalpath 252-c may provide the control signal to a demodulator 255-c and anaddress decoder 260-c. The demodulator 255-c may demodulate the controlsignal carried on the control signal path 252-c to obtain controlinformation. The control information may include commands for each ofthe control circuits 215 that are distributed to each of the controlcircuits 215 by the beam forming network 210-b. The commands fordifferent control circuits 215 may be serially transmitted in thecontrol information. That is, in addition to receiving its own controldata, the control circuit 215-c may receive and demodulate the controlinformation for each of the other control circuits 215 (e.g., forcontrol circuit 215-d). The control information may include addressinformation (e.g., in a header) identifying the address of theparticular control circuit 215 for which the corresponding controlinformation is intended. The address decoder 260-c may compare a knownaddress (as further discussed below) of the control circuit 215-c to theaddress information in the control data 226-b to identify the controlinformation that is intended for the particular control circuit 215-c,and provide the identified control information via a signal path 253-cto a corresponding adjustment circuit 265-c. The second control circuit215-d may operate similarly to the first control circuit 215-c, thesecond control circuit 215-b similarly including a demodulator 255-d, anaddress decoder 260-d, and an adjustment circuits 265-d (e.g., tosimilarly provide identified control information via a signal path 253-dto the adjustment circuit 265-d).

Each of the adjustment circuits 265 (e.g., adjustment circuit 265-c andadjustment circuit 265-d) may include one or more circuit elements(e.g., one or more phase shifters 270, one or more amplifiers 275, etc.)to provide, based on the identified control information, appropriateadjustments of amplitude and/or phase to the corresponding elementsignals. FIG. 4 shows a breakout view of the adjustment circuit 265-c.In the illustrated example, the adjustment circuit 265-c includes aphase shifter 270-b that applies a phase shift to the correspondingelement signal as indicated by the control information. In theillustrated example, the adjustment circuit 265-c further includes anamplifier 275-b that amplifies the phase shifted signal from the phaseshifter as indicated by the control information to produce an adjustedelement signal. The adjusted element signal may be provided via thesecond port 249 of the control circuit 215 to the corresponding antennaelement 220 for transmission. The transmissions of the adjusted elementsignals by each of the antenna elements 220 of the phase array antennatogether produce a transmit beam transmitted in a desired scan angledirection.

In some cases, each of the control circuits 215 may include multiplesets of beamforming registers. In some examples, each of the controlcircuits 215 includes double buffered beamforming registers so the nextadjustment values for the next upcoming beam pointing state (i.e., anupcoming beam direction for the transmit beam) can be loaded whileoperating in the current state. This may allow the phased array antennato change pointing directions relatively quickly, for example, insituations in which the phased array antenna is to alternate itspointing direction between two different receiving devices (e.g., forsatellite handover). Further, this may facilitate the phased arrayantenna to maintain its tracking direction of a receiving device in thecase in which beam-forming coefficients are frequency dependent andfrequency hopping is performed, for example, to maintain the beamdirection while alternating between two different frequency bands. Insome examples, each of the control circuits may include multiple sets ofregisters to store coefficients for beams used for mispointingcorrection (e.g., via step track, conical scan, monopulse tracking). Forexample, each of the control circuits may store sets of coefficientsassociated with a conical scan operation relative to the current beam.The conical scan may intentionally point the antenna beam away from thetarget direction according to different angular offsets and measure asignal attribute (e.g., via a received signal or feedback indicating asignal strength of a transmitted signal), adjusting the antenna beam toa new target direction if an improved signal attribute is found at ascan offset. As each mispointing correction operation is performed and anew beam directed to the target is selected as a result of the conicalscan, the sets of coefficients may be updated with new sets ofcoefficients for the next conical scan operation. In some cases, aportion (e.g., 10 bits) of the address headers may be reserved and usedas global commands such as “transmit enable/disable” and/or “receiveenable/disable,” commands to enable buffered beam weights fromparticular registers (e.g., registers A and B for double-bufferedbeamforming registers), and other commands for the phased array antenna.

In some cases, the control circuits 215 and the controller 225-b maysupport bi-directional communication. For example, each of the controlcircuits 215 may also have a modulator (not shown), which may be part ofthe demodulators, or separate components. Controller 225-b may send acommand to read a configured value (e.g., control information) from oneof the control circuits 215, and the addressed control circuit 215 maythen respond by modulating a signal with the response (e.g., theconfigured value) and multiplexing the modulated signal onto theindividual output signals 246 at the respective element signal port 245.The modulated signal may then be carried via the beam forming network210-b and the first routing circuit 205-b to the controller 225-b, whichmay then demodulate the signal and decode the response. Thus,bi-directional communication may allow for checking a configuration ofthe control circuits 215, or reading other status information from thecontrol circuits 215 for testing or debugging purposes.

In some cases, the demodulators 255 may recover the carrier (e.g., acarrier for the control signal) to generate a clock signal tosynchronize the different control circuits 215. For example, thedemodulator 255-e may use a carrier-recovery loop or other carrierrecovery techniques (e.g., compensating for frequency and/or phasedifferences between the control signal carrier and a local oscillator).The demodulator 255-e may then set a clock signal based on the recoveredwaveform. In this way, the clock signal may be synchronized between eachof the control circuits 215 of the phased array antenna. Thus, thecontrol signal may use coherent modulation, and the synchronized clocksignals at the demodulators 255 may use coherent demodulation todemodulate the control signal 231-b.

FIG. 5 illustrates an example diagram 500 of a circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna in accordance with aspects of the present disclosure. The phasedarray antenna may be an example of one or more of the antenna arrays140, as described with reference to FIG. 1. The phased array antenna ofFIG. 5 may be an example of a receive phased array antenna for receivingcommunication signals from the satellite 105, as described withreference to FIG. 1.

The circuit architecture for the phased array antenna in FIG. 5 mayoperate in a substantially similar way with similar or correspondingcomponents as described with reference to FIGS. 2 through 4, except asotherwise described herein. Although not illustrated, in some cases thephased array antenna of FIG. 5 may produce and pass a power signal assimilarly described with reference to FIG. 4, for example. The phasedarray antenna in FIG. 5 is an example of a receive phased array antennarather than the transmit phased array antennas described in FIGS. 2 and4. In the receive phased array antenna, the element signals are receivedat the antenna elements 220, and proceed through the signal paths in theopposite direction of transmit signals. That is, the antenna elements220 may receive corresponding receive element signals 266 (e.g., receiveelement signal 266-a and receive element signal 266-b) from atransmitting device (e.g., a satellite), which may be provided throughthe corresponding control circuits 215 to the beam forming network210-c. The beam forming network 210-c may combine these element signalsto create a receive beam signal, which may be passed through the firstrouting circuit 205-c to the processor and other devices at the airplane(or other vehicle) on which the phase array antenna is mounted.

As shown in FIG. 5, the circuit architecture includes a first routingcircuit 205-c, a beam forming network 210-c, multiple control circuits215, and multiple antenna elements 220. In the example of FIG. 5, afirst control circuit 215-e and a corresponding first antenna element220-e and a second control circuit 215-f and a corresponding secondantenna element 220-f are shown. It should be appreciated, however, thatany number N of control circuits 215 for antenna elements 220 may beimplemented similarly. As illustrated in FIG. 5, there is a one-to-onecorrespondence between control circuits 215 and antenna elements 220(i.e., there is a different control circuit 215 connected to eachantenna element 220). However, it is to be appreciated that in somecases one control circuit 215 may be shared among multiple antennaelements 220 (i.e., one control circuit 215 may be connected to, andreceive respective signaling from, multiple antenna elements 220). Eachof the components may be connected via signal paths.

As described herein, the control circuits 215, beam forming network210-c, first routing circuit 205-c, controller 225-a, and each of theother components and signal paths may support bi-directionalcommunication. For example, as described above, each of the controlcircuits 215 may also include modulators (not shown), which may be partof the demodulators 255, or separate components. Controller 225-c maysend a command to read a configured value (e.g., control information)from one of the control circuits 215, and the addressed control circuit215 may then respond by modulating a signal with the response (e.g., theconfigured value) and multiplexing the modulated signal onto theindividual output signals at the respective element signal ports 245 ofthe beam forming network 510-c. The modulated signal may then be carriedvia the beam forming network 210-c and the first routing circuit 205-cto the controller 225-a, which may then demodulate the signal and decodethe response. Thus, bi-directional communication may allow for checkinga configuration of the control circuits 215, or reading other statusinformation from the control circuits 215 for testing or debuggingpurposes. Additionally, in the case of the receive phased array antenna,bi-directional communication may support signal paths carrying controlsignals in one direction, and providing a receive element signal in theopposite direction.

In the receive phased array antenna, the antenna elements 220 mayreceive respective receive element signals 266 from a transmittingdevice (e.g., a satellite), and provide the receive element signals tothe control circuits 215. As described above, each control circuit 215may include a first port 248 (e.g., first port 248-e and first port248-f) connected to a corresponding element signal port 245 of the beamforming network 210-c and a second port 249 (e.g., second port 249-e andsecond port 249-f) connected to the corresponding antenna element 220.Each control circuit 215 may include a second routing circuit 250 (e.g.,a diplexer or other multiplexer, or other type of signal routingcircuit) that establishes an element signal path 251 (e.g., elementsignal path 251-e and element signal path 251-f) between the first port248 and the second port 249 of the control circuit 215 and a controlsignal path 252 (e.g., control signal path 252-e and control signal path252-f) between the first port 248 of the control circuit 215 and anadjustment circuit 265.

An adjustment may be applied to the receive element signals at theadjustment circuits 265 to generate adjusted element signals, asdescribed below. Each second routing circuit 250 may provide thecorresponding adjusted element signal (having a center frequency f_(rx))from the corresponding adjustment circuit 265 to the corresponding firstport 248, while also providing the control signal (having a centerfrequency f_(c)) from the corresponding first port 248 to thecorresponding control signal path 252. As such, the signal path betweenthe corresponding first port 248 and a corresponding element signal port245 of the beam forming network 210-c contains a multiplexed signalincluding the adjusted element signal and the control signal. In FIG. 5,each of the second routing circuits 250 is a diplexer including twobandpass filters 235—one for each of the signals. For example, in thesecond routing circuit 250-e, a first bandpass filter 235-o may allowsignals of a first frequency range to pass, where the first frequencyrange corresponds to at least the frequency range of the receive elementsignal. For example, the receive element signal may be modulated receivesignal including a modulating signal modulated with the carrier f_(rx)for the receive element signal. Although shown having a center frequencyequal to f_(rx), the center frequency of the first bandpass filter 235-omay not be the same as the carrier frequency f_(rx) for the receiveelement signal, as long as the first frequency range allows the receiveelement signal to pass (e.g., while excluding the control signal). Asecond bandpass filter 235-p may allow a second frequency range to pass,where the second frequency range corresponds to at least the frequencyrange of the control signal (e.g., the modulated control signal).Although shown having a center frequency equal to f_(c), the centerfrequency of the second bandpass filter 235-p may not be the same as thecarrier frequency f_(c) for the control signal, as long as the secondfrequency range allows the control signal to pass (e.g., while excludingthe receive element signal). Similarly, the second routing circuit 250-fmay include a first bandpass filter 235-q and a second bandpass filter235-r for the element signal and control signal, respectively.

In, for example, the first control circuit 215-e, the control signalpath 252-e may provide the control signal to a demodulator 255-e and anaddress decoder 260-e. The demodulator 255-e may demodulate the controlsignal carried on the control signal path 252-e to obtain controlinformation. The control information may include commands for each ofthe control circuits 215 (e.g., serial data) that are copied to each ofthe control circuits 215 by the beam forming network 210-c. That is, inaddition to receiving its own control data, the control circuit 215-emay receive and demodulate the control information for each of the othercontrol circuits 215 (e.g., for control circuit 215-f). The controlinformation may include address information (e.g., in a header)identifying the address of the particular control circuit 215 for whichthe corresponding control information is intended. The address decoder260-e may compare a known address (as further discussed below) of thecontrol circuit 215-e to the address information in the control data226-c to identify the control information that is intended for theparticular control circuit 215-e, and provide the identified controlinformation via a signal path 253-e to a corresponding adjustmentcircuit 265-e. The second control circuit 215-f may operate similarly tothe first control circuit 215-e, the second control circuit 215-fsimilarly including a demodulator 255-f, an address decoder 260-f, andan adjustment circuits 265-f (e.g., to similarly provide identifiedcontrol information via a signal path 253-f to the adjustment circuit265-f).

Each of the adjustment circuits 265 (e.g., adjustment circuit 265-e andadjustment circuit 265-f) may include one or more circuit elements(e.g., one or more phase shifters 270, one or more amplifiers 275, etc.)to provide, based on the identified control information, appropriateadjustments of amplitude and/or phase to the corresponding individualreceive element signals to generate individual adjusted element signals.FIG. 5 shows a breakout view of the adjustment circuit 265-e. In theillustrated example, the adjustment circuit 265-e includes a phaseshifter 270-c that applies a phase shift to the corresponding receiveelement signal as indicated by the control information. In theillustrated example, the adjustment circuit 265-e further includes anamplifier 275-e that first amplifies the individual receive elementsignal as indicated by the control information prior to the phaseshifter applying the phase shift. The adjustments may be applied to thereceive element signal 266-a to produce an adjusted element signal. Theadjusted element signal may be provided to the second routing circuit250-e, as described above.

The second routing circuits 250 may provide the adjusted element signalbi-directionally multiplexed with the control signal to an elementsignal port 245 (in this case, an input port with respect to the elementsignal and an output port with respect to the control signal) of thebeam forming network 210-c. The beam forming network 210-a may includeone or more stages of PCB combiner/dividers that combine the individualelement signals to provide a receive beam signal at a common signal port240-c. In the other direction, the first routing circuit 205-a mayprovide a control signal 231-c to the common signal port 240-c of thebeam forming network 210-c. The beam forming network 210-c may copy thecontrol signal 231-c containing the control data 226-c received at thecommon signal port 240-c to each of the element signal ports 245corresponding to each of the antenna elements 220. The beam formingnetwork 210-c may accordingly generate the individual control signals inthe individual combined (or multiplexed) signals 247 (e.g., combinedsignal 247-a and combined signal 247-b) at element signal ports 245(e.g., element signal port 245-e and element signal port 245-f) of thebeam forming network 210-c.

In sum, each bi-directional combined signal 247 at the respectiveelement signal ports 245 may include an individual receive elementsignal as an input to the beam forming network 210-c from the controlcircuits 215 and an individual control signal (e.g., a copy of thecontrol signal 231-c) as an output from the beam forming network 210-cto the control circuits 215. The bi-directional combined signal at thecommon signal port 240-c may include a composite receive beam signal asan output of the beam forming network 210-c to the first routing circuit205-c and a copy of the control signal 231-c as an output from the firstrouting circuit 205-c to the beam forming network 210-c.

The first routing circuit 205-c may receive the receive beam signal fromthe beam forming network 210-c. The first routing circuit 205-a mayfurther receive control data 226-c from the controller 225-c. Thecontrol data 226-a may indicate the adjustment values (e.g., amplitudeand/or phase) to be applied by the adjustment circuits 265, as describedherein, to receive the receive beam at a desired scan angle direction.

The phased array antenna may include a modulator 230-c that modulatesthe control data 226-c to produce the control signal 231-c. Themodulator 230-c may modulate the control data 226-c received from thecontroller 225-c and pass the modulated control signal 231-c to thefirst routing circuit 205-c. In some cases, the modulator 230-c may beimplemented within or as a component of the controller 225-c. Themultiplexer of the first routing circuit 205-c may receive the receivebeam signal from the beam forming network 210-c and receive the controlsignal 231-c (having a center frequency fc) from modulator 230-c. Assuch, the signal path between the first routing circuit 205-c and thebeam forming network 210-c contains a composite multiplexed signal 241-cincluding the receive beam signal and the control signal 231-c. Thefirst routing circuit 205-c may then send a receive beam signal 237-ato, for example, a reception processor to process the informationreceived by the phased array antenna.

As shown in FIG. 5, the first routing circuit 205-c is implemented as adiplexer including two bandpass filters 235. A first bandpass filter235-m may allow signals of a first frequency range to pass, where thefirst frequency range corresponds to at least a frequency range of thereceive beam signal. For example, the receive beam signal may be amodulated receive beam signal including a modulating signal modulatedwith the carrier f_(rx) for the receive beam signal. Although shownhaving a center frequency equal to f_(rx), the center frequency of thefirst bandpass filter 235-m may not be the same as the carrier frequencyf_(rx) for the receive beam signal, as long as the first frequency rangeallows the receive beam signal to pass (e.g., while excluding thecontrol signal). The second bandpass filter 235-n may allow signals of asecond frequency range to pass, where the second frequency rangecorresponds to at least the frequency range of the control signal 231-c(e.g., the modulated control signal). Although shown having a centerfrequency equal to f_(c), the center frequency of the second bandpassfilter 235-n may not be the same as the carrier frequency f_(c) for thecontrol signal, as long as the second frequency range allows the controlsignal to pass (e.g., while excluding the receive beam signal).Different possible implementations for the first routing circuit 205-cmay also be used, as described above.

FIG. 6 illustrates an example diagram 600 of a circuit architecture fordistributed multiplexed control and element signals for a phased arrayantenna in accordance with aspects of the present disclosure. The phasedarray antenna may be an example of one or more of the antenna arrays140, as described with reference to FIG. 1. The phased array antenna ofFIG. 6 may be an example of a transmit/receive phased array antenna thatmay both transmit communication signals to and receive communicationsignals from the satellite 105, as described with reference to FIG. 1.

The circuit architecture for the phased array antenna in FIG. 6 mayoperate in a substantially similar way with similar or correspondingcomponents as described with reference to FIGS. 2 through 5, except asotherwise described herein. While FIG. 6 shows only one control circuit215-g, it is to be appreciated that like FIGS. 2 through 5, there may beany number N of control circuits 215.

As shown in FIG. 6, an antenna element 220-g is a receive antennaelement 220 with a signal path connected to a receive adjustment circuit265-g. An antenna element 220-h is a transmit antenna element 220 with asignal path connected to a transmit adjustment circuit 265-h. It shouldbe appreciated that while FIG. 6 shows a separate transmit antennaelement 220 and receive antenna element 220, a single antenna element220 may be used for both transmission and reception.

As shown in FIG. 6, the circuit architecture includes a first routingcircuit 205-d, a beam forming network 210-d, a control circuit 215-g,and multiple antenna elements 220. In the example of FIG. 6, the controlcircuit 215-a and corresponding receive antenna element 220-g andtransmit antenna element 220-h are shown. It should be appreciated,however, that any number N of control circuits 215 for antenna elements220 may be implemented similarly. As illustrated in FIG. 6, there is aone-to-two correspondence between control circuits 215 and antennaelements 220. However, it is to be appreciated that in some cases onecontrol circuit 215 may be shared among multiple receive and transmitantenna elements 220 (i.e., one control circuit 215 may be connected to,and receive respective signaling from multiple receive antenna elements220 or provide signaling to multiple transmit antenna elements 220).Each of the components may be connected via signal paths.

The first routing circuit 205-d (e.g., a diplexer or other multiplexer,or other type of signal routing circuit) may receive a transmit beamsignal 236-c from, for example, a transmission processor, to betransmitted as a transmit beam by the phased array antenna. The firstrouting circuit 205-d may receive a receive beam signal from the beamforming network 210-c as may have been received by the phased arrayantenna as described herein. The first routing circuit 205-d may furtherreceive a control signal 231-d from a modulator 230-d that containscontrol data 226-d from a controller 225-d. The control data 226-d mayindicate adjustment values (e.g., amplitude and/or phase) for one ormore of the N control circuits 215 to be applied by respective controlcircuits to transmit the transmit beam signal and to receive the receivebeam signal in desired scan angle directions.

The phased array antenna may include the modulator 230-d that modulatesthe control data 226-d to produce the control signal 231-d. Themodulator 230-d may modulate the control data 226-a received from thecontroller 225-d and pass the modulated control signal 231-d to thefirst routing circuit 205-d. In some cases, the modulator 230-d may beimplemented within or as a component of the controller 225-d. Asmentioned above, the inputs to the first routing circuit 205-d mayinclude the transmit beam signal 236-c (having a center frequencyf_(tx)), the composite receive beam signal (having a center frequencyf_(rx)), and the control signal 231-d (having a center frequency f_(c)).Thus, as shown in FIG. 6, the composite multiplexed signal 241-d is abi-directional signal, with the control signal and transmit beam signalbeing in one direction (from the first routing circuit 205-d to the beamforming network 210-d) and the receive beam signal being in the oppositedirection (from the beam forming network 210-d to the first routingcircuit 205-d).

The first routing circuit 205-d may generate components of compositemultiplexed signal 241-d including the transmit beam signal 236-c andthe control signal 231-d. The composite multiplexed signal 241-d may bemultiplexed over the composite receive beam signal traveling on thesignal path in the other direction to the first routing circuit 205-dfrom the beam forming network 210-c. The first routing circuit 205-d mayfurther send a receive beam signal 237-b to, for example, a receptionprocessor to process the information received by the phased arrayantenna.

As shown in FIG. 6, the first routing circuit 205-a is a triplexer (or acombination of diplexers) including three bandpass filters 235—one foreach respective signal. A first bandpass filter 235-s may allow signalswithin a first frequency range to pass, where the first frequency rangecorresponds to at least the frequency range of the transmit beam signal236-c (e.g., the modulated transmit beam signal). Although shown havinga center frequency equal to f_(tx), the center frequency of the firstbandpass filter 235-s may not be the same as the carrier frequencyf_(tx) for the transmit beam signal, as long as the first frequencyrange allows the transmit beam signal 236-c to pass (e.g., whileexcluding the control signal 231-d and the modulated receive beamsignal). The second bandpass filter 235-t may allow a frequency band ofa second frequency range to pass, where the second frequency rangecorresponds to at least the frequency range of the receive beam signal237-b (e.g., the modulated receive beam signal). Although shown having acenter frequency equal to f_(rx), the center frequency of the secondbandpass filter 235-t may not be the same as the carrier frequencyf_(rx) for the receive beam signal, as long as the second frequencyrange allows the receive beam signal 236-a to pass (e.g., whileexcluding the control signal and the transmit beam signal). The thirdbandpass filter 235-u may allow signals within a third frequency rangeto pass, where the third frequency range corresponds to at least thefrequency range of the control signal 231-d (e.g., the modulated controlsignal). Although shown having a center frequency equal to f_(c), thecenter frequency of the third bandpass filter 235-u may not be the sameas the carrier frequency f_(c) for the control signal, as long as thethird frequency range allows the control signal to pass (e.g., whileexcluding the transmit beam signal and the receive beam signal).Different possible implementations for the first routing circuit 205-dmay also be used, as described above.

The first routing circuit 205-d may provide the transmit beam signal236-c multiplexed with the control signal 231-d to a common signal port240-d of the beam forming network 210-d. In the reverse direction, thereceive beam signal 237-b may also be multiplexed with the compositemultiplexed signal 241-d and received by the first routing circuit205-d. The beam forming network 210-d may include one or more stages ofPCB combiner/dividers that divide the transmit components of compositemultiplexed signal 241-c to produce individual output signals 246 atoutput element signal ports 245 of the beam forming network 210-d. Thatis, the beam forming network 210-c may divide the composite multiplexedsignal 241-c into individual output signals 246 (e.g., individual outputsignal 246-g), each output signal 246 including an individual transmitelement signal (e.g., a copy of transmit beam signal 236-c) and anindividual control signal (e.g., a copy of control signal 231-d). Theone or more stages of PCB dividers may provide relative amplitude and/orphase shifts between the individual element signals of the individualoutput signals 246 as part of the overall beamforming of the phasedarray antenna. In such a case, the individual control signals of theindividual output signals 246 may also experience relative amplitudeand/or phase shifts due to the one or more stages of PCB dividers.However, such relative shifts in amplitude and/or phase shifts areapplied to the carriers of the individual control signals and thus donot impact the control data 226-d. In addition, these shifts may notimpact recovery of the carrier of the individual control signals forsynchronization (as discussed below), as the precision needed may besignificantly less than is needed for the individual element signals.The control data 226-d may include information for each of the controlcircuits 215 (e.g., serial data), and the beam forming network 210-d maycopy the control signal 231-d received at the common signal port 240-dto the element signal ports 245. The individual transmit element signalincluded in each individual output signal 246 at the respective elementsignal ports 245 may subsequently be adjusted by a corresponding controlcircuit 215 connected to the corresponding element signal port 245 andtransmitted by a corresponding antenna element 220. Similarly, in thereverse direction, the beam forming network 210-d may combine individualadjusted element signals received at the element signal ports 245 toprovide the receive beam signal 237-b at the common signal port 240-d.

The transmit and receive individual output signals 246-g at the elementsignal port 245-g may include the individual element signals (e.g.,transmit and receive element signals) multiplexed with the individualcontrol signal (e.g., a copy of the control signal 231-d). The controlsignal may be used by the corresponding control circuit 215 to applyappropriate adjustment (e.g., amplitude and/or phase) to thecorresponding transmit and receive element signals. That is, the beamforming network 210-c may divide the composite multiplexed signal 241-cto generate individual control signals and individual transmit elementsignals at the element signal port 245-g. In the reverse direction andusing the same stages of PCB combiner/dividers that divide the compositemultiplexed signal 241-d, the beam forming network 210-d may combineindividual receive element signals at the element signal ports 245 toprovide the composite receive beam signal 237-b at the common signalport 240-d. The individual control signals may be multiplexed with thecorresponding receive and transmit element signals to form themultiplexed individual output signal 246-g. By multiplexing the elementsignals and the control signal, the beam forming network 210-d may beused to generate and distribute the transmit element signals and thecontrol signals indicating control data for each of the correspondingelement signals for each antenna element 220 of the control circuit215-g.

The control circuit 215-g may include a first port 248-g connected tothe corresponding element signal port 245-g of the beam forming network210-d, a second port 249-g connected to the receive antenna element220-g, and a third port 254 connected to the transmit antenna element220-h. The control circuit 215-g may include a second routing circuit250-g (e.g., a triplexer or other multiplexer, or other type of signalrouting circuit) that establishes a receive element signal path 251-gbetween the first port 248-g and the second port 249-g of the controlcircuit 215-g, a transmit element signal path 251-h between the firstport 248-g and the third port 254 of the control circuit 215-g, and acontrol signal path 252-g between the first port 248-g of the controlcircuit 215-g and adjustment circuits 265 (e.g., receive adjustmentcircuit 265-g and transmit adjustment circuit 265-h).

As shown in FIG. 6, the second routing circuit 250-g is a triplexer thatdemultiplexes (e.g., via frequency demultiplexing) the transmit elementsignal and control signal into corresponding individual element andcontrol signals. As correspondingly described with reference to thefirst routing circuit 205-d that multiplexes signals, the second routingcircuit 250-g may perform analogous inverse operations using analogouscomponents to demultiplex the signals. The second routing circuit 250-gmay further receive an adjusted receive element signal from the receiveantenna element 220-g via the receive adjustment circuit 265-g. Thesecond routing circuit 250-g may include a first bandpass filter 235-vthat may allow signals within a first frequency range to pass, where thefirst frequency range corresponds to at least the frequency range of thetransmit element signal (e.g., the modulated transmit beam signal).Although shown having a center frequency equal to f_(tx), the centerfrequency of the first bandpass filter 235-v may not be the same as thecarrier frequency f_(tx) for the transmit beam signal, as long as thefirst frequency range allows the transmit element signal to pass (e.g.,while excluding the control signal and the modulated receive beamsignal). The second bandpass filter 235-w may allow a frequency band ofa second frequency range to pass, where the second frequency rangecorresponds to at least the frequency range of the receive elementsignal (e.g., the modulated receive beam signal). Although shown havinga center frequency equal to f_(rx), the center frequency of the secondbandpass filter 235-w may not be the same as the carrier frequencyf_(rx) for the receive element signal, as long as the second frequencyrange allows the receive element signal to pass (e.g., while excludingthe control signal and the transmit beam signal). The third bandpassfilter 235-x may allow signals within a third frequency range to pass,where the third frequency range corresponds to at least the frequencyrange of the control signal (e.g., the modulated control signal).Although shown having a center frequency equal to f_(c), the centerfrequency of the third bandpass filter 235-x may not be the same as thecarrier frequency f_(c) for the control signal, as long as the thirdfrequency range allows the control signal to pass (e.g., while excludingthe transmit beam signal and the receive beam signal). The secondrouting circuit 250-g may provide the adjusted receive element signal,in the opposite direction, with the individual output signal 246-g toprovide the adjusted receive element signal to the output element signalport 245-g of the beam forming network 210-d. As described above, otherpotential implementations may be used, including the use of other PCBtraces, components including high- and low-pass filters, capacitors,inductors, and the like.

In the control circuit 215-g, the control signal path 252-g may runthrough a demodulator 255-g, an address decoder 260-g, and respectivereceive and transmit adjustment circuits 265. The demodulator 255-g maydemodulate the control signal carried on the control signal path 252-gto obtain control information. The control information may includecommands for the control circuits 215 that are then distributed to eachof the control circuits 215 by the beam forming network 210-d. That is,in addition to receiving its own control data, the control circuit 215-gmay receive and demodulate the control information for each of the othercontrol circuits 215. The control information may include addressinformation (e.g., in a header) identifying the address of theparticular control circuit 215 for which the corresponding controlinformation is intended. The address decoder 260-g may compare a knownaddress (as further discussed below) of the control circuit 215-g to theaddress information in the control data 226-d to identify the controlinformation that is intended for the particular control circuit 215-gand its corresponding receive antenna element 220-g and transmit antennaelement 220-h. The address decoder 260-g may provide the identifiedcontrol information via signal paths 253 to the corresponding adjustmentcircuits 265. For example, the address decoder 260-g may provide controlinformation via a signal path 253-g for a receive beam adjustment to thereceive adjustment circuit 265-g and control information via a signalpath 253-h for a transmit beam adjustment to the transmit adjustmentcircuit 265-h. As described herein, the adjustment circuits 265 mayinclude one or more circuit elements (e.g., one or more phase shifters270, one or more amplifiers 275, etc.) to provide, based on theidentified control information, an appropriate adjustment of amplitudeand/or phase to the corresponding element signal. The adjustmentsapplied to the element signals for each of the antenna elements 220 ofthe phase array antenna together produce transmit and receive beams indesired scan angle directions.

In some cases, the control circuit 215-g and the controller 225-d maysupport further bi-directional communication (e.g., bi-directionalcommunication of control information in addition to bi-directionalcommunication of element signals). For example, the control circuit215-g may also have a modulator (not shown), which may be part of thedemodulator 255-g, or a separate component. Controller 225-d may send acommand to read a configured value (e.g., control information) from oneof the control circuits 215 (e.g., the control circuit 215-g) and theaddressed control circuit 215 may respond by modulating a signal withthe response (e.g., the configured value) and multiplexing the modulatedsignal onto the individual output signal 246-g at the respective elementsignal port 245-g. The modulated signal may then be carried via the beamforming network 210-d and the first routing circuit 205-d to thecontroller 225-d, which may then demodulate the signal and decode theresponse. Thus, further bi-directional communication may allow forchecking a configuration of the control circuits 215-g, or reading otherstatus information from the control circuits 215 for testing ordebugging purposes.

FIG. 7 illustrates an example diagram 700 of multi-layer PCB 705 for acircuit architecture for distributed multiplexed control and elementsignals for a phased array antenna in accordance with aspects of thepresent disclosure. The phased array antenna may be an example of one ormore of the antenna arrays 140, as described with reference to FIG. 1,and the circuit architecture for distributed multiplexed control andelement signals for a phased array antenna as described with referenceto FIGS. 2 and 4 through 6. The phased array antenna of FIG. 7 may be anexample of a transmit phased array antenna for transmittingcommunication signals to the satellite 105, as described with referenceto FIG. 1, and the circuit architecture for distributed multiplexedcontrol and element signals for a phased array antenna as described withreference to FIGS. 2, 4, and 6. The circuit architecture for the phasedarray antenna in FIG. 7 may operate in substantially the same way withsimilar or corresponding components as described with reference to FIGS.2, 4, and/or 6. Further, while FIG. 7 shows a transmission operation ofa phased array antenna, the phased array antenna may be configured forreception, as described with reference to FIG. 5.

As shown in FIG. 7, the multi-layer PCB 705 may include one or moresections 710, including a first section 710-a including controlcircuits, a second section 710-b including a beam forming network, and athird section 710-c including antenna elements 220. Each section 710 mayinclude one or more PCB layers. It should be understood that while thesethree sections are only one example implementation of a multi-layer PCB705 for the described circuit architecture, and that otherimplementations may be used, such as with different components ondifferent PCB layers in different sections 710, etc.

In the example shown in FIG. 7, the first routing circuit 205-e and eachof the control circuits 215 are located the bottom side of a bottomlayer of the multi-layer PCB 705. A signal path 708 (e.g., a signalpath 1) is shown as the dashed line from first routing circuit 205-e toan antenna element 220-i. The first routing circuit 205-e outputs acomposite multiplexed signal 715 (including a transmit beam signal and acontrol signal) onto via 720-a, where the via 720-a is connected to aconductive trace on a layer 725. The signal path 708 carrying thecomposite multiplexed signal 715 may then be input into a beam formingnetwork including multiple stages of PCB dividers 730 that divide thecomposite multiplexed signal 715 to produce individual multiplexedsignals at respective element signal ports 245. For example, a first PCBdivider 730-a of the beam forming network may provide a firstmultiplexed control and element signal to a first element signal port245-h intended for the first antenna element 220-i via a first controlcircuit 215-h, a second PCB divider 730-b of the beam forming networkmay provide a second multiplexed control and element signal to a secondelement signal port 245-i intended for a second antenna element 220-jvia a second control circuit 215-i, and so on.

As shown in the example implementation of FIG. 7, at the element signalport 245-h (i.e., an output port 1), an individual multiplexed signal718 may carry multiplexed individual control and element signalsintended for the antenna element 220-i. Via 720-b is connected to theelement signal port 245-h of the beam forming network and carries theindividual multiplexed signal 718 (i.e., an individual multiplexedsignal 1 including an element signal 1 and a corresponding controlsignal) to the input of the control circuit 215-h (i.e., a controlcircuit 1). As discussed above, the control circuit 215-h may demodulatethe control signal and identify the control information addressed to it.The control circuit 215-h may provide the identified control informationto its corresponding adjustment circuit which adjusts the element signal1 in phase and/or amplitude based on the control information to producean adjusted individual element signal 722. The adjusted individualelement signal 722 may be provided at the output of the control circuit215-h onto via 720-c and carried to the antenna element 220-i fortransmission.

FIG. 8 illustrates an example diagram 800 of an addressing architecturefor distributed multiplexed control and element signals for a phasedarray antenna in accordance with aspects of the present disclosure. Theaddressing architecture may be an example of addressing architecture forone or more of the address decoders 260 as described with references toFIGS. 2 and 4 through 6. The example diagram 800 illustrates multiplecontrol circuits 215-j arrayed in rows and columns on a PCB of anantenna array.

Each control circuit 215-j of the antenna array may recognize its ownaddress by reading address voltage levels, for example using an ADC. Asshown in FIG. 8, the addressing architecture includes a column voltagedivider 805 and a row voltage divider 810. The column voltage divider805 may include one or more columns 815 from a supply voltage 820-a to avoltage ground 825. The column voltage divider 805 may include a numberm of column voltage divider elements 830 (e.g., resistor voltagedividers), where the combination of column voltage divider elements 830may divide the supply voltage to obtain the resulting column voltages850 for each column 815. The row voltage divider 810 may also include anumber n of rows 835 from a supply voltage 820-b to the voltage ground825. The row voltage divider 810 may include one or more row voltagedivider elements 840 (e.g., resistor voltage dividers), where thecombination of row voltage divider elements 840 may divide the supplyvoltage to obtain the resulting row voltages 855 for each row 835.

Each control circuit 215-j may be located at a position in one of thecolumns 815 coupled to one of the column voltages 850. Similarly, eachaddress element 845 lies at a position in one of the rows 835 coupled toone of the row voltages 855. In this way, each control circuit 215-j maybe located at a respective unique combination of row and columnaddresses. Each control circuit 215-j may include a row address pin thatreceives the corresponding row voltage and a column address pin thatreceives the corresponding column voltage. ADCs may then be used to readthese voltages at the row and column address pins, thus identifying theparticular control information (e.g., particular beam adjustmentcoefficients for amplitude and/or phase) intended for the correspondingantenna element. The illustrated addressing architecture may use arelatively lower pin-count versus using pull-up/down or open/shortaddress strapping, which may reduce PCB area and cost for each controlcircuit.

As described above, in some cases, the addresses of the control circuitsmay be selected (e.g., using sequential row and column addresses) suchthat if a control circuit applies control information for an incorrectlydecoded address, the control information applied by the control circuitis likely intended for one of the adjacent control circuits (i.e., acontrol circuit may at (m, n) apply control information intended for anantenna element at (m, n+1) or (m, n−1). Where row and column voltagelevels are used for addressing of control circuits, errors in readingthe row or column address voltage may also apply control informationintended for an adjacent or proximate control circuit. In these cases,the adjustments indicated by the control information of, for example, anadjacent control circuit 215 may not substantially differ from theadjustment indicated for the actual location of the control circuit 215.For example, one control circuit 215 would apply an adjustment (e.g., ofphase and/or amplitude) intended for its nearest neighboring controlcircuit 215 by row and/or column, which may not substantially degradethe RF beam forming performance of some antenna arrays.

In some cases, and as described above, the control signal and the beamsignal may be provided to the beam forming network concurrently.However, in some cases, a controller may not provide the control signalcontinuously and/or not concurrently with the beam signal. Rather, insome cases, the controller may provide the control information from timeto time as needed to reconfigure the phased array antenna to change adesired scan angle direction.

The various illustrative blocks and components (e.g., the controllers225, the modulators 230, and/or each of the various components of thefirst routing circuits 205 and the control circuits 215) described inconnection with the disclosure herein may be implemented or performedwith a general-purpose processor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described herein. Ageneral-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, for example, acombination of a DSP and a microprocessor, multiple microprocessors,microprocessors in conjunction with a DSP core, or any other suchconfiguration

The detailed description set forth above in connection with the appendeddrawings describes exemplary embodiments and does not represent the onlyembodiments that may be implemented or that are within the scope of theclaims. The term “example” used throughout this description means“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other embodiments.” The detailed descriptionincludes specific details for the purpose of providing an understandingof the described techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand devices are shown in block diagram form in order to avoid obscuringthe concepts of the described embodiments.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The functions described herein may be implemented in various ways, withdifferent materials, features, shapes, sizes, or the like. Otherexamples and implementations are within the scope of the disclosure andappended claims. Features implementing functions may also be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations.Also, as used herein, including in the claims, “or” as used in a list ofitems (for example, a list of items prefaced by a phrase such as “atleast one of” or “one or more of”) indicates a disjunctive list suchthat, for example, a list of “at least one of A, B, or C” means A or Bor C or AB or AC or BC or ABC (i.e., A and B and C).

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the scope of thedisclosure. Thus, the disclosure is not to be limited to the examplesand designs described herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A phased array antenna system, comprising: a beamforming network to convert between a plurality of element signals at aplurality of element signal ports and a beam signal at a common signalport, the beam forming network being located on one or more layers of aprinted circuit board (PCB); a first signal routing circuit to provide acontrol signal from a controller to the common signal port, wherein thebeam forming network distributes the control signal to each of theplurality of element signal ports; and a plurality of control circuitslocated on a first layer of the PCB, each control circuit having a firstport coupled to a corresponding element signal port of the plurality ofelement signal ports and a second port coupled to a correspondingantenna element, the antenna elements corresponding to each of thecontrol circuits being located on a second layer of the PCB, each of theplurality of control circuits comprising: a second signal routingcircuit coupled to the first port, the second signal routing circuit toestablish an element signal path for a corresponding element signal ofthe plurality of element signals communicated between the first port andthe second port, and to establish a control signal path for the controlsignal received via the first port, and a first signal adjustmentcircuit along the element signal path and the control signal path, thefirst signal adjustment circuit to adjust the corresponding elementsignal based at least in part on the control signal.
 2. The phased arrayantenna system of claim 1, wherein the first signal routing circuitcomprises: a multiplexer that multiplexes the control signal and thebeam signal to generate a composite multiplexed signal comprising thecontrol signal and the beam signal.
 3. The phased array antenna systemof claim 2, wherein the control signal and the beam signal occupynon-overlapping frequency bands.
 4. The phased array antenna system ofclaim 2, wherein the composite multiplexed signal further comprises apower signal multiplexed with the control signal and the beam signal. 5.The phased array antenna system of claim 4, wherein each control circuitof the plurality of control circuits comprises a decoupler to obtain thepower signal for supplying power to each of the control circuits.
 6. Thephased array antenna system of claim 1, wherein the first signal routingcircuit further provides a power signal to the common signal port,wherein the beam forming network distributes the power signal to each ofthe plurality of element signal ports.
 7. The phased array antennasystem of claim 6, wherein the beam signal comprises a receive beamsignal and the power signal is multiplexed with the receive beam signal.8. The phased array antenna system of claim 2, wherein the beam formingnetwork converts between the composite multiplexed signal and aplurality of individual multiplexed signals at the plurality of elementsignal ports.
 9. The phased array antenna system of claim 8, wherein thesecond signal routing circuit of each of the plurality of controlcircuits demultiplexes one of the plurality of individual multiplexedsignals to obtain the control signal and the corresponding elementsignal of the plurality of element signals.
 10. The phased array antennasystem of claim 1, wherein the second signal routing circuit comprises:a multiplexer that multiplexes a respective control signal from thefirst port of the respective control circuit to the first signaladjustment circuit and a respective element signal from the second portof the respective control circuit to the first port of the respectivecontrol circuit.
 11. The phased array antenna system of claim 10,wherein the beam forming network converts the control signal at thecommon signal port to a plurality of individual control signals at theelement signal ports and from a plurality of individual multiplexedsignals at the element signal ports to a composite multiplexed signal atthe common signal port.
 12. The phased array antenna system of claim 11,wherein the first signal routing circuit demultiplexes the compositemultiplexed signal to obtain the beam signal.
 13. The phased arrayantenna system of claim 1, wherein the beam forming network comprisesone or more combiner/dividers between the common signal port and theplurality of element signal ports, the one or more combiner/dividersbeing located on the one or more layers of the PCB.
 14. The phased arrayantenna system of claim 1, wherein the control signal comprises aplurality of adjustment values and corresponding address indicators,wherein each of the address indicators identifies an address of one ofthe control circuits of the plurality of control circuits for which thecorresponding adjustment value of the control signal is intended. 15.The phased array antenna system of claim 14, wherein each of theplurality of control circuits identifies its respective address based atleast in part on respective coupling of a plurality of address pins. 16.The phased array antenna system of claim 14, wherein each of theplurality of control circuits identifies its respective address based atleast in part on one or more of a row voltage obtained by a row voltagedivider, a column voltage obtained by a column voltage divider, or acombination thereof, each row voltage divider comprising a plurality ofrow voltage divider elements and each column voltage divider comprisinga plurality of column voltage divider elements.
 17. The phased arrayantenna system of claim 14, wherein adjacent control circuits of theplurality of control circuits have addresses, the addresses having asingle different address bit value.
 18. The phased array antenna systemof claim 14, wherein the address indicators comprise at least one errorcorrection bit.
 19. The phased array antenna system of claim 1, whereinthe first signal adjustment circuits of the plurality of controlcircuits apply respective first signal adjustments to respective elementsignals to obtain respective ones of a plurality of adjusted elementsignals.
 20. The phased array antenna system of claim 19, wherein thebeam signal comprises a receive beam signal, and the beam formingnetwork combines the plurality of adjusted element signals to obtain thereceive beam signal.
 21. The phased array antenna system of claim 19,wherein the beam signal comprises a transmit beam signal, and the beamforming network divides the transmit beam signal to obtain the pluralityof element signals, and wherein the respective adjusted element signalsare transmitted by the corresponding antenna elements.
 22. The phasedarray antenna system of claim 19, wherein the first signal adjustmentcircuit comprises an amplifier to apply an amplitude adjustment, a phaseshifter to apply a phase adjustment, or a combination thereof.
 23. Thephased array antenna system of claim 19, wherein the controllerdetermines a second signal adjustment and provides the second signaladjustment to the respective control circuit while the first signaladjustment circuit is operating according to the first signaladjustment, the second signal adjustment to be applied subsequent to thefirst signal adjustment.
 24. The phased array antenna system of claim23, wherein the first signal adjustment and the second signal adjustmentare associated with different frequency bands.
 25. The phased arrayantenna system of claim 1, wherein the first signal adjustment circuitsof the plurality of control circuits comprise receive adjustmentcircuits to adjust a receive element signal received via thecorresponding antenna element, and wherein each of the plurality ofcontrol circuits comprises a transmit signal adjustment circuit toadjust a transmit element signal to be transmitted via the correspondingantenna element.
 26. The phased array antenna system of claim 25,wherein each of the corresponding antenna elements comprises a firstantenna element coupled with the receive element signal and a secondantenna element coupled with the transmit element signal.
 27. The phasedarray antenna system of claim 1, wherein the antenna elements comprisepatch antennas located on the second layer of the PCB.
 28. The phasedarray antenna system of claim 1, wherein the first layer of the PCB andthe second layer of the PCB are a same layer.